Originally Posted by
qrpory
Thanks for the replies, I think I needed to be clearer though.
I'm trying to make a one-way "Miles" (show price in) booking, for example from PVG to CTU on the delta.com website for 8th May 2018.
When I click Find Flights, I can see a flight for Economy(X) for 12,500 miles or First Class(A) for 17,500 miles.
I click the First Class option and see MU5417 flight option. Clicking View Seats and it shows the First Seats greyed out but some economy seats available.
So my confusion is, I seem to be able to select a First flight and view available seats but they're all in economy with First greyed out.
If you are buying an award ticket for China Eastern (MU) you will not be able to select the seats through DL so don't worry what you are seeing. You have to do it through their website after purchase.
What is confusing is that you mention X and A and those are paid tickets, not tickets using miles.
BTW I'm trying to buy a similar ticket PVG-HKG for June 1 through DL in business class (o) and it doesn't appear to be available.